• Study: Covid-19 death rates higher in countries with bad air pollution
원문출처 : https://www.cnn.com/2020/04/07/health/mammal-human-virus-spillover-coronavirus-scn-wellness/index.html
원문출처 : https://www.cnn.com/2020/04/07/health/mammal-human-virus-spillover-coronavirus-scn-wellness/index.html